Fix regex patterns allowing for empty strings #7281
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This patch changes the mode we search for patterns which allow an empty string, by anchoring all searches. As a result we will match the longest possible match when multiple patterns are present (like `;*|rust`), instead of using the leftmost pattern only. This is only possible with empty matches since our parser is reset on every byte anyway, so anchoring the search makes no difference. Closes alacritty#7276.
kchibisov
approved these changes
Oct 9, 2023
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This patch changes the mode we search for patterns which allow an empty string, by anchoring all searches. As a result we will match the longest possible match when multiple patterns are present (like
;*|rust), instead of using the leftmost pattern only.This is only possible with empty matches since our parser is reset on every byte anyway, so anchoring the search makes no difference.
Closes #7276.
In theory this would allow us to split the parsers (so
regex_search_internal) completely for empty and non-empty patterns. This would probably speed up the non-empty version but I'm not sure it is worse the mess.